1. Field of the Invention
The present invention relates to resin compositions that can be preferably used for sealing and the like of an OLED (organic light emitting diode) device.
2. Discussion of the Background
An OLED (organic light emitting diode) device is a luminescent device using an organic substance as a luminescence material, and is a material attracting attention in recent years since it can provide high brightness luminescence at a low voltage. However, OLED (organic light emitting diode) devices are extremely vulnerable to moisture, and are associated with problems in that the organic material itself is deteriorated by moisture to show decreased luminance, fail to emit light, the interface between electrode and OLED (organic light emitting diode) layer is detached by the influence of moisture, and the metal is oxidized to have high resistance.
When a thermoset resin composition is used as a whole surface sealing material, advantages are that lamination work is easy since material viscosity is low before curing, and water vapor transmission of a cured product after thermal curing is low. On the other hand, however, an OLED (organic light emitting diode) device is problematically degraded by a heating temperature for thermal curing.
JP-A-2009-524705 discloses a sealing film comprising a polyisobutylene resin and a hydrogenated cyclic olefin based polymer. While the film is generally laminated with a protective film, since the film has a high tackiness, the protective film is difficult to detach, and the handling is extremely difficult since it is markedly deformed during detachment and the like.
On the other hand, JP-A-2008-248055 discloses a composition for a sealing material, which contains an isobutylene polymer an epoxy group-containing compound, and a curing agent for epoxy resin. However, since this composition requires hot-melt application, a sheet cannot be produced conveniently like a varnish coating. In addition, JP-A-2008-248055 is silent in regard to adhesion and handling properties, and sufficient consideration has not been conducted.
Thus, there remains a need for resin compositions that can be used for sealing and the like of an OLED (organic light emitting diode) device which do not suffer from the above-discussed drawbacks.